Yarn texturing apparatus and fluid diffuser therefor



p 12, 1967 D. SHICHMAN 3,340,684

YARN TEXTURIZING APPARATUS AND FLUID DIFFUSER THEREFOR Filed Dec. -'7, 1965 I NVEN'TOR.

V7 DAN/EL JH/CHMA/V BY I L B MPM AI TOBNEY United States Patent 3,340,684 YARN TEXTURING APPARATUS AND FLUID DIFFUSER THEREFOR Daniel Shichman, Cedar Grove, N.J., assignor to Uniroyal, Inc., a corporation of New Jersey Filed Dec. 7, 1965, Ser. No. 512,088 18 Claims. (Cl. 5734) This invention relates to yarn texturizing apparatus, and in particular to diffusing attachments for use with the fluid false twisters of such apparatus.

In US. Patent No. 3,204,396 issued to B. H. Foster and R. H. Hugger on Sept. 7, 1965, there is disclosed a texturizing apparatus for thermoplastic yarn which comprises a hot air oven through which the yarn is passed at a predetermined rate, and a fluid twister located near the yarn exit of the oven for imparting a twist to the yarn, the arrangement being such that the twist travels back along the yarn through the heating zone defined in the hot air oven. The eflect of the heat is to soften the yarn and thereby to cause the twist to be set therein, whereby the yarn receives a crimp-like texture and a corresponding softness of feel or hand, as well as an increase in bulk and elasticity. As dislcosed in the said Foster and Hugger patent, the twister is so constructed that the principal flow of the false-twisting fluid leaving the twister is directed countercurrent to the movement of the yarn therethrough, i.e. toward the yarn exit of the hot air oven, and that it is possible to false-twist multi-filament thermoplastic yarn at speeds approaching 1000 feet per minute.

Under such operating conditions, of course, each given increment of the yarn being treated is exposed to the heating zone for only a relatively short interval of time during which it must be softened sufiiciently to permit the twist to be set in the yarn. By the very nature of the arrangement, however, a substantial amount of the relatively cool fluid employed in the false twister leaves the latter in a narrow stream through the nozzle defining the yarn entrance of the twister and flows directly into the yarn exit of the heating oven. A cooling of the exit region of the heating zone thus results (temperature measurements in that region have, in fact, indicated that the temperature in the last one-third of the heating zone is generally lowered by as much as 100 F.). This in effect shortens the length of the zone available for heatsetting the yarn, whereby the latter is subjected to a less than optimum softening action, which tends to make proper and uniform yarn texturizing diflicult. Avoidance of this drawback by raising the temperature in the heating oven has not proved eflicacious, inasmuch as the greater expenditure of energy has an adverse effect on the economy of the operation, while the raising of the ambient temperature in the cooled exit region of the heating Zone up to the proper level concomitantly entials raising the temperature in the remainder of the zone to a level far above the maximum usable limit.

It is an important object of the present invention, therefore, to provide means in a yarn texturizing apparatus of this type facilitating a material reduction in the quantity of relatively cool false-twisting fluid entering the heating zone.

A particular object of the present invention is the provision of an attachment for the fluid false twister of such apparatus by means of which the major portion of the stream of fluid issuing from the twister is diffused laterally of the yarn path and thereby prevented from entering the yarn exit region of the heating zone.

Another object of the present invention is the provision of such a fluid-diffusing attachment which enables the entire yarn texturizing operation to be rendered considerice ably more economical by permitting an operation of the heating zone at temperatures considerably lower than the standard temperatures required for achieving the same amount of heat set in the yarn.

The foregoing and other objects, characteristics and advantages of the present invention will be more clearly understood from the following detailed description thereof when read in conjunction with the accompanying drawing, in which:

FIG. 1 is a diagrammatic, partly sectional, fragmentary illustration of a yarn texturizing apparatus equipped with a diffuser attachment constructed in accordance with one embodiment of the present invention;

FIG. 2 is a plan view of the diffuser attachment shown in FIG. 1; and

FIGS. 3 and 4 are axial sections through diffuser at- 1 tachments constructed in accordance with slightly modified embodiments of the present invention.

Referring now first to FIG. 1, it will be seen that the apparatus 10 in connection with which the present invention finds its greatest advantage comprises a fluid twister 11 and a hot air heating oven 12 defining in conjunction with a plurality of yarn guide elements 13 (only one is shown) the path of movement of a filamentary thermoplastic strand or yarn 14 to be fed in the direction of the arrows A and B from a suitable supply package (not shown) to a take-up spool or package (not shown). The oven 12 defines a heating zone for the yarn.

The twister 11 generally comprises an interior hollow body 15 defining the plenum chamber in which the yarn is false-twisted. Merely by way of example, the body 15 may have a square outer configuration in the walls of which are provided respective off-center inlet openings 16 establishing communication between an inner cylindrical bore (not shown) of the body 15 and an outer lateral entrance passageway 17 through which compressed air or other suitable pressurized fluid flows in the direction of the arrow C. The openings 16 thus communicate with the said cylindrical bore substantially tangentially of the latter, thereby producing a vortical flow of the fluid within the plenum chamber suflicient to impart a twist to the yarn 14. This twist travels back along the yarn through the heating zone up to the yarn guide 13 and is thus set in the yarn due to the thermoplastic nature of the latter.

Although some of the high pressure fluid introduced into the twister 11 leaves the plenum chamber through the yarn exit 11a of the twister, i.e. in the direction of the arrow B, the principal part of the fluid flows out of the twister through the yarn entrance 11b thereof, i.e. countercurrent to the direction of yarn movement. As previously indicated, it is the basic object of the present invention to prevent this stream of relatively cool fluid from traveling directly into the exit end region of the heating zone defined in the proximate part of the oven 12.

To this end, a diffuser nozzle or member 18 designed, in a manner to be more fully described presently, to divert the major portion of the efliuent stream of fluid essentially laterally away from the path of yarn movement and thus away from the yarn exit of the heating zone, is positioned about the fluid exit 11b of the twister. As clearly shown in FIGS. 1 and 2, the diffuser member 18 comprises a body 19 which is externally threaded and terminates at one end in a head 20 of somewhat larger outer diameter. Preferably the outer peripheral surface of the head 20 is knurled or otherwise shaped to enable the member 18 to be tightly gripped by hand or with the aid of a wrench or other tool when screwing the body '19 into or out of a corresponding internally threaded extension of the twister 11.

The diffuser member 18 is axially bored throughout its entire length, the bore comprising an end section 21 large enough to accommodate the fluid exit nozzle 11b of the twister and communicating at its innermost extremity with a relatively narrow throat-like section 22 which in turn communicates with an essentially conically flaring section 23. In the diffuser according to this embodiment of the invention the wall defining the bore section 23 has, in sequence, a conical portion 23a, a cylindrical portion 23b, a conical portion 23c, a cylindrical portion 23d and a final conical portion 23a at the outermost end of the head 20. Essentially within the region of the cylindrical portion 23b, i.e. at the junction between the body 19 and head 20, the member 18 is further provided with a plurality of lateral openings 24 which are oriented (see FIG. 2) in radial planes relative to the axis of the member 18 and preferably obliquely with respect to the axis of the bore 21-22 23. It will be understood, of course, that the openings 24 need not be obliquely oriented as shown in FIGv 1, but may have their axes oriented substantially perpendicular to the bore axis, as indicated at 24' for the member 18' shown in FIG. 4. Optimally, for the purposes of the present invention, it is preferred to provide either three or four such openings spaced equidistantly from each other circumferentially of the diffuser member, although it will be apparent that for some variations of the diffuser design and attendant operating conditions, a different number of openings arranged at approximately the illustrated degree of obliquity may also give satisfactory results.

In a representative construction of a diffuser member 18, the same measures in overall axial length, with the axial dimensions of the bore sections 21, 22 and 23a to 236 being %.2", a". %2, %4, %4", /32" and A6", respectively. Concurrently, the outer diameters of the body 19 (measured at the thread apices) and head 20 are /2 and /8", respectively, the inner diameters of the cylindrical bore sections 21, 22, 23b and 23d are and /2", respectively, and the taper of each of the conical surfaces 23a, 23c and 23e is 45 relative to the axis of the member 18. Three openings 24 are spaced 120 apart, each having a diameter of and its axis oriented at an angle of about 60 to the axis of the bore 21-22-23 so as to diverge in the direction of the head 20 of the diffuser. If four openings 24 are provided, these will, of course, be spaced 90 apart, while if they are oriented as in FIG. 4, the distance between the common plane of their axes and the end edge plane of the head 20 is It will be understood that the inner surface configuration of the generally conically flaring bore section may be varied from that illustrated in FIGS. 1, 2 and 4. Merely by way of example, as shown in FIG. 3 at 25 for the diffuser member 18", this section may be continuously tapered from the bore section 21 to the end edge plane of the head 20, or the part of the bore section above the openings may be continuously tapered from the cylindrical wall portion 23b to the end edge plane of the head 20. Also, the openings in such a diffuser member could be oriented as in FIG. 4 rather than obliquely as in FIG. 3.

When the diffuser member 18 is to be used in a yarn texturizing operation, the head 119 thereof is screwed into the internally threaded extension 110 of the twister 11 until the fluid exit portion 11b of the latter extends into the bore section 21 to an extent sufficient to leave a small clearance of about & between the annular bottom of the bore section 21 and the outermost end face of the fluid exit nozzle 11b. Preferably also a radial clearance between about 0.002" and about 0.010" is maintained between the outer peripheral surface of the nozzle 1 11) and the surrounding wall of the bore section 21.

With such an arrangement, the stream of fluid which leaves the plenum chamber within the body 15 countercurrent to the direction of yarn movement and after having performed its yarn twisting function, is found to flow along arcuate flow paths indicated by the curved arrows in FIG. 1, so as to leave the diffuser member in part through the openings 24 (or 24') and in part laterally over the outermost rim of the head 20. The principal part of this relatively cool fluid thus is diffused laterally away from the path of movement of the yarn and does not enter the heating zone in the oven 12. Actual measurements have shown that with this type of arrangement, the temperature in the exit end region of the heating zone can be: maintained with a few degrees Fahrenheit of the tempera-- ture over the balance of the heating zone, which greatly increases the length of the path through which the yarn is. subjected to the proper heat-setting temperatures. At thesame time it has been found that since the actual heatsetting path is lengthened to the full longitudinal dimension of the heating zone, it is possible to employ temperatures as much as 80 F. below the temperatures normally employed in the apparatus disclosed in the aforesaid Foster and Hugger patent.

The provision of the diffuser member 18 (or 18' or 18") according to the present invention is further advantageous in that it facilitates diffusing the fluid laterally away from the yarn path without engendering any turbulence which could interfere with the false twisting of the yarn. At the same time, the provision of the generally conically flaring bore section 23 (or 25) ensures that sufficient space is available for the yarn or strand 14 to balloon properly, as indicated in broken lines in FIG. 1, without coming into contact with any part of the diffuser surface (which, at the high feed and twisting speeds employed, would immediately cause the yarn or strand to be ruptured, necessitating a shut-down and rethreading of the apparatus).

The principles and advantages of the present invention are further illustrated by the following examples.

Example I For the purpose of processing a denier 34 filament Du Pont No. 288 nylon yarn in the apparatus 10- at a feed-in speed of 860 feet per minute, a take-up speed of 820 feet per minute, and a wind-up speed of 795 feet per minute, using compressed air as the twisting fluid, the air pressure in the twister 11 was set at 70 p.s.i., and the temperature controller for the heating zone was set at 550 F. The diffuser employed was the three-opening member 18 shown in FIGS. 1 and 2. With this arrangement, the temperature deviation in the heating zone was found to be about 3 F.

Example 11 Under the same operating conditions as in Example I, but employing a diffuser member 18 provided with four openings 24, the temperature deviation in the heating zone was found to be about 7 F.

Example III A diffuser 18 was employed in which the inner bore surface 25 from the bore section 22 to the end edge plane of the heat 20 was conical, as shown in FIG. 3. The lateral openings were oriented as in FIG. 4. The temperature deviation in the heating zone was found to be 3 F. in the case of the three-opening diffuser and 4 F. in the case of the four-opening diffuser.

As will be readily appreciated, the present invention is applicable to the treatment of single-filament as well as multi-filament thermoplastic fiber strands, irrespective of the denier thereof, which it is desired to crimp by setting a false twist therein. The filamentary strands thus may be made from superpolyamides such as nylon, ethers and organic acid esters of cellulose such as ethyl cellulose, cellulose acetate, cellulose triacetate, cellulose propionate, cellulose butyrate, cellulose acetate formate, and the like, polyesters such as polyethylene terephthalate, polyolefins such as polyethylene, polypropylene, and the like, acrylonitrile polymers and copolymers, vinyl polymers and copolymers such as polyvinyl acetate, polyvinyl chloride, polyvinylidene chloride, polyvinyl acetate-vinyl chloride, and the like, and other synthetic fibers of a thermoplastic nature.

It will also be understood that any suitable gaseous fluid under high pressure may be utilized as the vortically flowing twisting medium. Preferably, but not necessarily, the fluid is air. Although a dry fluid would ordinarily be employed, high pressure steam may be used if desired and not found harmful to the filamentary strand material or to the setting of the false twist therein. Further, although the invention is set forth in an environment employing a fluid flow countercurrent to the direction of yarn movement, the operation of the diifuser would be the same in the case of a fluid flow codirectional with the yarn movement.

It is to be understood that the foregoing description of preferred aspects of the present invention is for purposes of illustration only, and that the structural and operational features and relationships disclosed herein are susceptible to modifications and variations none of which entails any departure from the spirit and scope of the present invention as defined in the hereto appended claims.

Having thus described my invention, what I claim and desire to protect by Letters Patent is:

1. An apparatus for texturizing thermoplastic filamentary strand material, comprising means defining a heating zone, means for guiding a thermoplastic filamentary strand through said heating zone, fluid twister means positioned adjacent one end of said heating zone for through passage of said strand and operable upon creation of a vortical flow of high pressure fluid therethrough to impart a false twist to each given increment of length of said strand concomitantly with the passage thereof through said heating zone, said fluid twister means being provided with a strand-passing fluid exit nozzle the outlet of which is directed toward said heating zone, and mean operatively interposed between said fluid exit nozzle and said one end of said heating zone for diffusing the fluid issuing from said nozzle laterally away from the path of movement of said strand intermediate said heating zone and said fluid twister means, thereby to reduce materially the amount of such fluid entering said heating zone.

2. An apparatus according to claim 1, said diifusing means comprising a member provided with a through bore flaring generally conically from a relatively narrowest portion adjacent said outlet of said fluid exit nozzle to a relatively widest portion at the end of said member remote from said outlet.

3. An apparatus according to claim 2, said member being further provided with a plurality of lateral openings located intermediate the ends of said bore and spaced from each other peripherally of said member.

4. An apparatus according to claim 3, said openings being equidistantly spaced from each other around said member.

5. An apparatus according to claim 3, said member being provided with three openings spaced at 120 intervals around said member.

6. An apparatus according to claim 3, said member being provided with four openings spaced at 90 intervals around said member.

7. An apparatus according to claim 1, said dilfusing means comprising a member secured to said fluid twister means and provided with a through bore, said bore having a first section receiving said fluid exit nozzle and further having a second relatively narrow section positioned in close proximity to said outlet of said nozzle when the latter is received in said first section, said bore further having a third section flaring generally conically from. a narrowest end portion adjoining said second section to a widest end portion at the end of said member remote from said nozzle.

8. An apparatus according to claim 7, said member being further provided with a plurality of lateral openings located intermediate the end portions of said third section of said bore and spaced from each other peripherally of said member.

9. An apparatus according to claim 8, said openings being equidistantly spaced from each other around said member.

10. An apparatus according to claim 8, said member being provided with three openings spaced at 120 intervals around said third section of said bore.

11. An apparatus according to claim 8, said member being provided with four openings spaced at intervals around said third section of said bore.

12. An apparatus according to claim 8, the axes of said openings being oriented obliquely away from the axis of said bore as viewed from said second section of said bore toward the remote end portion of said third section of said bore.

13. An apparatus according to claim 8, the axes of said openings being oriented in a common plane at right angles to the axis of said bore.

14. A fluid diifuser member adapted to be interposed between an exit nozzle of a fluid twister and an adjacent zone which is to be kept substantially free of said fluid, said diffuser member comprising a body defining a generally conically flaring passageway adapted to be aligned with said nozzle, said body being provided intermediate the ends of said passageway with a plurality of lateral openings, whereby any fluid issuing from said nozzle and entering said passageway at the narrower end thereof is diverted both through said openings and over the wide end rim of said body essentially laterally of said body, thereby enabling a material reduction in the amount of such fluid able to enter said zone to be achieved.

15. A fluid diifuser member according to claim 14, said body being provided with a through bore having a first section adapted to receive said nozzle and with a second section defining said generally conically flaring passageway.

16. A fluid diffuser member according to claim 14, said body being provided with a through bore having a first section adapted to receive said nozzle, said bore further having a second relatively narrow section contiguous with said first section and a third section defining said generally conically flaring passageway extending from said second section to said wide end rim of said body.

17. A fluid diffuser member according to claim 16, the axes of said openings being oriented obliquely to the axis of said bore and diverging from each other in a direction away from said second section of said bore.

18. A fluid diffuser member according to claim 16, the axes of said openings being oriented in a common plane at right angles to the axis of said bore.

References Cited UNITED STATES PATENTS 2,379,824 7/ 1945 Mummery 19-66 3,031,733 5/1962 Ljung et a1 281 3,035,313 5/1962 Naegeli et al 19-157 X 3,173,188 3/1965 Wexler 28-1 3,204,396 9/1965 Foster et a1 5777.3 X

FRANK I. COHEN, Primary Examiner. J. PETRAKES, Assistant Examiner. 

1. AN APPARATUS FOR TEXTURING THERMOPLASTIC FILAMENING ZONE, MEANS FOR GUIDING A THERMOPLASTIC FILAMENTARY STRAND THROUGH SAID HEATING ZONE, FLUID TWISTER MEANS POSITIONED ADJACENT ONE END OF SAID HEATING ZONE FOR THROUGH PASSAGE OF SAID STRAND AND OPERABLE UPON CREATION OF A VOTICAL FLOW OF HIGH PRESSURE FLUID THERETHROUGH TO IMPART A FALSE TWIST TO EACH GIVEN INCREMENT OF LENGTH OF SAID STRAND CONCOMITANTLY WITH THE PASSAGE THEREOF THROUGH SAID HEATING ZONE, SAID FLUID TWISTER MEANS BEING PROVIDED WITH A STRAND-PASSING FLUID EXIT NOZZLE THE OUTLET OF WHICH IS DIRECTED TOWARD SAID HEATING ZONE, AND MEANS OPERATIVELY INTERPOSED BETWEEN SAID FLUID EXIT NOZZLE AND SAID ONE END OF SAID HEATING ZONE FOR DIFFUSING THE FLUID ISSUING FROM SAID NOZZLE LATERALLY AWAY FROM THE PATH OF MOVEMENT OF SAID STRAND INTERMEDIATE SAID HEATING ZONE AND SAID FLUID TWISTER MEANS, THEREBY TO REDUCE MATERIALLY THE AMOUNT OF SUCH FLUID ENTERING SAID HEATING ZONE.
 14. A FLUID DIFFUSER MEMBER ADAPTED TO BE INTERPOSED BETWEEN AN EXIT ZONE NOZZLE OF A FLUID TWISTER AND AN ADJACENT ZONE WHICH IS TO BE KEPT SUBSTANTIALLY FREE OF SAID FLUID, SAID DIFFUSER MEMBER COMPRISING A BODY DEFINING A GENERALLY CONICALLY FLARING PASSAGEWAY ADAPTED TO BE ALIGNED WITH SAID NOZZLE, SAID BODY BEING PROVIDED INTERMEDIATE 